Drying treatment device

Abstract

To propose a drying treatment device which enables reduction of steps of a processing method of used batteries including a drying treatment step for removing an electrolyte from fragments of the batteries containing the electrolyte.SOLUTION: A drying treatment device includes: a housing having a slot for placing fragments into the device, and a discharging port for discharging the fragments; a screw conveyor including a screw blade provided in an internal space of the housing, and a driving device that drives the screw blade, the screw conveyor configured to convey the fragments placed from the slot to the discharging port using pushing-out action of the screw blade; and a heater that heats the housing. In the drying treatment device, the driving device drives the screw blade while the heater is heating the housing.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a technique for drying crushed battery fragments containing an electrolyte solution so as to vaporize the electrolyte solution. [Background technology]

[0002] Patent Document 1 discloses a technology relating to a method for disposing of used lithium-ion batteries. Patent Document 1 discloses a method for disposing of lithium-ion batteries that includes a step of drying crushed pieces (pulverized material) of lithium-ion batteries and a step of transporting the dried crushed pieces to a transport container using transportation equipment (conveyor).

[0003] Other examples of documents that demonstrate the state of the art in the technical fields related to the present disclosure include the following Patent Documents 2 to 4. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-052213 [Patent Document 2] Japanese Patent Application Publication No. 08-117719 [Patent Document 3] Japanese Patent Application Laid-Open No. 2003-200146 [Patent Document 4] Japanese Patent Application Laid-Open No. 2002-273400 Summary of the Invention [Problem to be solved by the invention]

[0005] As disclosed in Patent Document 1, there is a processing method including a step of performing a drying process for removing an electrolytic solution from crushed pieces of a battery containing the electrolytic solution as a method for processing a used battery. Since the drying process is required to sufficiently remove the electrolytic solution, it is a process that takes a considerable amount of time. Therefore, in such a processing method, there is a possibility that the step of performing the drying process and the step of transporting to the next processing step may become the rate-determining process. One object of the present disclosure is to provide a technique that enables shortening of steps with respect to a processing method including a step of performing a drying process.

Means for Solving the Problems

[0006] One aspect of the present disclosure relates to a drying processing apparatus that vaporizes an electrolytic solution from crushed pieces of a battery containing the electrolytic solution. The drying processing apparatus includes a housing having an inlet for introducing the crushed pieces and an outlet for discharging the crushed pieces, a screw blade provided in the internal space of the housing, and a driving device for driving the screw blade, and a screw conveyor that conveys the crushed pieces introduced from the inlet to the outlet by the pushing action of the screw blade, and a heater for heating the housing. The drying processing apparatus drives the screw blade by the driving device while the heater is heating the housing.

Effects of the Invention

[0007] According to the present disclosure, the drying processing apparatus can convey the crushed pieces introduced into the housing from the inlet to the outlet while performing a drying process for vaporizing the electrolytic solution from the crushed pieces. Thereby, the drying process step and the conveying step can be integrated. As a result, in a processing method including a drying process step, effective shortening of steps can be achieved.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each figure, the same or corresponding parts are denoted by the same reference numerals, and the description thereof is simplified or omitted.

[0010] 1 Overview Used batteries are processed through various treatment steps for the purpose of recycling or disposal. In particular, in the treatment of used batteries, it is required to appropriately remove and recover the electrolytic solution contained in the batteries. For this reason, as a method for treating used batteries, there is a treatment method including a treatment step (drying treatment step) of vaporizing the electrolytic solution from the crushed pieces containing the electrolytic solution by drying the crushed pieces of the battery. In the drying treatment step, the crushed pieces of the battery are held in an atmosphere of temperature and pressure according to the vaporization conditions of the electrolytic solution. The present embodiment relates to a drying treatment apparatus for carrying out the drying treatment step.

[0011] By the way, when moving from the previous treatment step to the next treatment step, usually, the object to be treated is conveyed from the treatment apparatus of the previous treatment step to the treatment apparatus of the next treatment step. That is, between each treatment step, there is usually a step (conveying step) of conveying the object to be treated.

[0012] The drying treatment apparatus according to the present embodiment can integrate the drying treatment step and the conveying step in a treatment method including the drying treatment step. The drying treatment step is a treatment step that requires a considerable amount of time to sufficiently remove the electrolytic solution. Therefore, integrating the drying treatment step and the conveying step realizes an effective shortening of the entire treatment process. Hereinafter, the drying treatment apparatus according to the present embodiment will be described in detail.

[0013] 2 Drying Treatment Apparatus Fig. 1 is a diagram showing the configuration of a drying processing device 10 according to the present embodiment. Fig. 2 shows the operation of the drying processing device 10 according to the present embodiment based on the configuration shown in Fig. 1.

[0014] The drying treatment device 10 according to this embodiment includes a housing 100, a heater 200, a decompression pump 300, an electrolyte recovery device 400, and a screw conveyor 500.

[0015] The housing 100 has an internal space in which a screw blade 510 of a screw conveyor 500 (described later) is provided, and has a shape extending along the axial direction of the screw blade 510. The housing 100 is formed, for example, from a steel material with high thermal conductivity. In particular, the housing 100 may have a portion of its internal space curved downward to ensure pressure resistance. More specifically, the internal space may be formed so that when the housing 100 is cut in a direction perpendicular to the axial direction of the screw blade 510, the bottom wall surface and left and right side wall surfaces constituting the internal space form a U-shape. FIGS. 1 and 2 show a side view of the internal space of the housing 100. Note that in practice, a ceiling wall surface is provided constituting the internal space. FIGS. 1 and 2 also show a case in which the housing 100 is installed in an inclined position. However, in the drying processing device 10 according to this embodiment, the installation state of the housing 100 can be changed as appropriate.

[0016] The housing 100 has an inlet 110 and an outlet 120. The inlet 110 and the outlet 120 are respectively provided near both ends of the screw blade 510. In FIGS. 1 and 2, the inlet 110 is provided on the front surface of the housing 100 on the left end side of the screw blade 510. The outlet 120 is provided on the bottom surface of the housing 100 on the right end side of the screw blade 510. The positions of the inlet 110 and the outlet 120 may be changed as appropriate.

[0017] Battery fragments 1 containing electrolyte are fed into the housing 100 through an inlet 110. The fragments 1 are obtained, for example, by crushing frozen batteries in a previous processing step. Examples of batteries to be crushed include lithium-ion batteries, nickel-metal hydride batteries, and nickel-cadmium batteries. A hopper may be connected to the inlet 110 to facilitate the feeding of the fragments 1.

[0018] The crushed pieces 1 put into the housing 100 become the processing target of the drying processing device 10. In the drying processing device 10, a heater 200 and a decompression pump 300 are driven to perform a drying process in which the electrolyte is evaporated from the crushed pieces 1.

[0019] The heater 200 heats the housing 100. The structure of the heater 200 is not particularly limited. For example, the heater 200 is made of an electric heating wire. The heater 200 is driven so that the temperature of the internal space of the housing 100 rises to a certain temperature according to the vaporization conditions of the electrolyte solution.

[0020] The decompression pump 300 is connected to the internal space of the housing 100 via pipes 20a and 20b. However, an electrolyte recovery device 400 is provided between the housing 100 and the decompression pump 300. The operation of the electrolyte recovery device 400 will be described later.

[0021] The decompression pump 300 is a pump that decompresses the internal space of the housing 100. The decompression pump 300 can also be called a "vacuum pump." The decompression pump 300 decompresses the internal space of the housing 100 by sucking air from the housing 100 through the pipes 20a and 20b. The decompression pump 300 is driven to decompress the internal space of the housing 100 to a certain pressure according to the vaporization conditions of the electrolyte while the heater 200 is heating the housing 100.

[0022] By heating with the heater 200 and depressurizing with the vacuum pump 300, the internal space of the housing 100 maintains the temperature and pressure at which the electrolytic solution contained in the crushed pieces 1 vaporizes. Therefore, as the temperature of the crushed pieces 1 introduced into the housing 100 rises to the maintained temperature, the electrolytic solution gradually vaporizes from the crushed pieces 1. In this way, in the drying treatment apparatus 10, a drying treatment for vaporizing the electrolytic solution from the crushed pieces 1 containing the electrolytic solution is performed.

[0023] In the drying treatment apparatus 10, further, by the action of the electrolytic solution recovery device 400, the electrolytic solution removed from the crushed pieces 1 by the drying treatment is recovered.

[0024] The electrolytic solution recovery device 400 is connected to the pipes 20a and 20b and is provided between the housing 100 and the vacuum pump 300. The gaseous electrolytic solution 2a vaporized by the drying treatment flows into the electrolytic solution recovery device 400 through the pipe 20a by the intake of the vacuum pump 300. The electrolytic solution recovery device 400 maintains the temperature and pressure at which the gaseous electrolytic solution 2a condenses. That is, the electrolytic solution recovery device 400 condenses the inflowing gaseous electrolytic solution 2a. Then, the electrolytic solution recovery device 400 recovers the condensed electrolytic solution 2b. In this way, in the drying treatment apparatus 10, it is possible to recover the electrolytic solution removed from the crushed pieces 1 by the drying treatment.

[0025] In the drying treatment apparatus 10, further, by the screw conveyor 500, the crushed pieces 1 are conveyed from the inlet 110 to the outlet 120 during the drying treatment of the crushed pieces 1.

[0026] The screw conveyor 500 includes a screw blade 510 and a drive device 520. The screw blade 510 is rotatably provided around the axis in the internal space of the housing 100. The screw blade 510 is formed of, for example, a steel material with high heat conductivity similar to the housing 100. The drive device 520 drives the screw blade 510. The drive device 520 is, for example, an electric motor attached to rotate the screw blade 510 around the axis.

[0027] When the drive unit 520 drives the screw blade 510, the screw blade 510 acts to push out the crushed pieces 1 in the axial direction from the internal space of the housing 100. The screw conveyor 500 transports the crushed pieces 1 from the inlet 110 to the outlet 120 by this pushing action of the screw blade 510.

[0028] In this embodiment, the screw conveyor 500 may be a shaftless screw conveyor. In other words, the screw blade 510 is formed without a shaft. The crushed pieces 1 fed into the housing 100 may each have a certain degree of particle size, and these particle sizes may differ from one another. In such a case, by making the screw conveyor 500 a shaftless type, the crushed pieces 1 are prevented from becoming entangled in the screw blade 510 during transport, allowing for smooth transport. However, depending on the degree of particle size of the crushed pieces 1, the screw conveyor 500 may also be a shafted screw conveyor.

[0029] In the drying processing device 10, the drive device 520 drives the screw blade 510 while the heater 200 heats the housing 100. As a result, the crushed pieces 1 are transported from the inlet 110 to the outlet 120 while being dried. The drive device 520 may be controlled by a control device (not shown) so that the crushed pieces 1 are sufficiently dried during transport. For example, the control device controls the drive device 520 to adjust the rotation speed of the screw blade 510 so that the transport time meets the processing time for the drying process. Also, for example, the control device controls the drive device 520 to adjust the rotation speed of the screw blade 510 depending on the amount of electrolyte recovered by the electrolyte recovery device 400.

[0030] The crushed pieces 1 transported while being dried are discharged from the discharge outlet 120 of the housing 100. In this way, in the drying processing device 10, the crushed pieces 1 are transported from the input port 110 to the discharge outlet 120 while the crushed pieces 1 are being dried.

[0031] As described above, in the drying apparatus 10 according to the present embodiment, the housing 100 in which the drying process of the crushed pieces 1 is performed also serves as a conveyance path from the inlet 110 to the outlet. Therefore, the drying apparatus 10 can perform the drying process and the conveyance process from the previous process to the next process. For example, the inlet 110 can be connected to the outlet of the processing apparatus in the previous process, and the outlet 120 can be connected to the inlet of the processing apparatus in the next process. In this way, according to the drying apparatus 10 according to the present embodiment, the drying process and the conveyance process can be integrated. As a result, in the processing method including the drying process, an effective shortening of the entire process can be realized.

[0032] In the drying apparatus 10 according to the present embodiment, the drying process is performed by heating the crushed pieces 1 to that temperature in the internal space of the housing 100 maintained at a constant temperature. However, since the internal space of the housing 100 is under reduced pressure, there is a possibility that sufficient temperature rise cannot be obtained only by heating the crushed pieces 1 by the atmosphere. Therefore, hereinafter, a configuration for more efficiently heating the crushed pieces 1 with respect to the drying apparatus 10 according to the present embodiment will be proposed.

[0033] 3 Configuration for Efficiently Heating Crushed Pieces FIG. 3 is a diagram for explaining a configuration for efficiently heating the crushed pieces 1 in the internal space of the housing 100. FIG. 3 is a cross-sectional view when the housing 100 is cut in a direction orthogonal to the axial direction of the screw blade 510, and is also a cross-sectional view of the housing 100 as viewed from the front surface on the inlet 110 side.

[0034] First, in the configuration shown in FIG. 3, the heater 200 is configured to heat the outer wall surface 101 of the housing 100 along the axial direction of the screw blade 510 (the conveyance direction of the screw conveyor 500). For example, the heater 200 is composed of a heating wire installed on the entire outer wall surface 101 of the housing 100.

[0035] 3, the bottom wall surface constituting the inner wall surface 102 of the housing 100 is curved convexly downward, so that this bottom wall surface and the left and right side wall surfaces constituting the inner wall surface 102 form a U-shaped cross section. The outer edge of the screw blade 510 is configured to abut against the bottom wall surface. In FIG. 3, the lower portion of the outer edge of the screw blade 510 abuts against the curved portion of the bottom wall surface.

[0036] The entire wall surface of the housing 100 along the axial direction of the screw blade 510 is heated by the heater 200. Therefore, the outer edge of the screw blade 510 abuts against the curved portion of the bottom wall surface, thereby efficiently transferring heat from the housing 100. As a result, the screw blade 510 is heated to a temperature approximately the same as that of the housing 100.

[0037] 3, the entire outer wall surface 101 of the housing 100 is heated by the heater 200 along the axial direction of the screw blade 510. Furthermore, when the outer edge of the screw blade 510 abuts the curved portion of the bottom wall surface, the screw blade 510 is heated to a temperature approximately the same as that of the housing 100. As a result, in the internal space of the housing 100, the crushed pieces 1 are heated using both the housing 100 and the screw blade 510 as heat sources between the inlet 110 and the outlet 120. In this way, the configuration described in FIG. 3 makes it possible to efficiently heat the crushed pieces 1.

[0038] Furthermore, in order to efficiently heat the crushed pieces 1, the housing 100 may be configured such that the distance between the crushed pieces 1 and the inner wall surface 102 of the housing 100 is equal to or less than a certain distance. As the distance from the inner wall surface 102 of the housing 100 increases, the heat transfer to the crushed pieces 1 is considered to weaken. Therefore, by configuring the distance between the crushed pieces 1 and the inner wall surface 102 to be equal to or less than a certain distance, it is possible to prevent insufficient heating of a part of the crushed pieces 1. Due to the action of the screw blades 510, it is assumed that the crushed pieces 1 are located below the center of the screw blades 510 in the internal space of the housing 100. Therefore, this configuration can be realized by keeping the distance d1 (the vertical distance from the center of the screw blades 510 to the bottom surface of the housing 100) and the distance d2 (the horizontal distance from the center of the screw blades 510 to the side surface of the housing 100) shown in FIG. 3 equal to or less than a certain distance. For example, the housing 100 is configured such that the distances d1 and d2 are each 100 mm or less.

Explanation of Signs

[0039] 1 Crushed pieces 10 Drying treatment device 100 Housing 110 Inlet 120 Outlet 200 Heater 300 Vacuum pump 400 Electrolyte recovery device 500 Screw conveyor 510 Screw blades 520 Driving device

Claims

1. A drying treatment device for vaporizing an electrolyte from crushed pieces of a battery containing the electrolyte, comprising: a housing having an inlet for introducing the crushed pieces and an outlet for discharging the crushed pieces; a screw conveyor including screw blades provided in the internal space of the housing and a driving device for driving the screw blades, the screw conveyor conveying the crushed pieces introduced from the inlet to the outlet by the pushing action of the screw blades; a heater for heating the housing; and wherein while the heater is heating the housing, the driving device drives the screw blades Drying treatment device.

2. The drying treatment device according to Claim 1, further comprising: a vacuum pump connected to the housing for reducing the pressure in the internal space; and wherein while the heater is heating the housing, the vacuum pump is driven Drying treatment device.

3. The drying treatment device according to Claim 2, further comprising: an electrolyte recovery device provided between the housing and the vacuum pump for condensing and recovering the electrolyte in a gaseous state Drying treatment device.

4. The drying treatment device according to any one of Claims 1 to 3, wherein the inner wall surface of the housing forming the internal space includes a bottom wall surface that is convexly curved downward toward the bottom of the housing; the heater is configured to heat the outer wall surface of the housing along the axial direction of the screw blades; and the outer edge portion of the screw blades is configured to contact the curved portion of the bottom wall surface Drying treatment device.

5. The drying treatment device according to any one of Claims 1 to 3, wherein the screw conveyor is a shaftless screw conveyor Drying treatment device.

Images